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<b>DbEnv::dbremove</b>
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<tt>
<b><pre>
#include &lt;db_cxx.h&gt;
<p>
int
DbEnv::dbremove(DbTxn *txnid,
    const char *file, const char *database, u_int32_t flags);
</pre></b>
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<b>Description: DbEnv::dbremove</b>
<p>The DbEnv::dbremove method removes the database specified by the
<b>file</b> and <b>database</b> parameters.  If no <b>database</b>
is specified, the underlying file represented by <b>file</b> is
removed, incidentally removing all of the databases it contained.</p>
<p>Applications should never remove databases with open <a href="../api_cxx/db_class.html">Db</a> handles,
or in the case of removing a file, when any database in the file has an
open handle.  For example, some architectures do not permit the removal
of files with open system handles.  On these architectures, attempts to
remove databases currently in use by any thread of control in the system
may fail.</p>
<p>The DbEnv::dbremove method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>database</b><ul compact><li>The <b>database</b> parameter is the database to be removed.</ul>
 <b>file</b><ul compact><li>The <b>file</b> parameter is the physical file which contains the
database(s) to be removed.</ul>
<p>When using a Unicode build on Windows (the default), the <b>file</b>
argument will be interpreted as a UTF-8 string, which is equivalent to
ASCII for Latin characters.</p>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b><a name="DB_AUTO_COMMIT">DB_AUTO_COMMIT</a></b><ul compact><li>Enclose the DbEnv::dbremove call within a transaction.  If the call succeeds,
changes made by the operation will be recoverable.  If the call fails,
the operation will have made no changes.</ul>
<br></ul>
 <b>txnid</b><ul compact><li>If the operation is part of an application-specified transaction, the
<b>txnid</b> parameter is a transaction handle returned from
<a href="../api_cxx/txn_begin.html">DbEnv::txn_begin</a>; if the operation is part of a Berkeley DB Concurrent Data Store group, the
<b>txnid</b> parameter is a handle returned from
<a href="../api_cxx/env_cdsgroup_begin.html">DbEnv::cdsgroup_begin</a>; otherwise NULL.
If no transaction handle is
specified, but the
DB_AUTO_COMMIT flag is specified,
the operation will be implicitly transaction protected.
</ul>
<br>
<br><b>Environment Variables</b>
<p>The 
environment variable <b>DB_HOME</b> may be used as the path of the
database environment home.</p>
<p>DbEnv::dbremove is affected by any database directory specified using
the <a href="../api_cxx/env_set_data_dir.html">DbEnv::set_data_dir</a> method, or by setting the "set_data_dir" string
in the environment's <a href="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file.</p>
<br><b>Errors</b>
<p>The DbEnv::dbremove method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If DbEnv::dbremove called before <a href="../api_cxx/env_open.html">DbEnv::open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
<br>
<br>
<b>ENOENT</b><ul compact><li>The file or directory does not exist.</ul>
<br>
<p>If a transactional database environment operation was selected to
resolve a deadlock, the DbEnv::dbremove method will fail and
either return <a href="../ref/program/errorret.html#DB_LOCK_DEADLOCK">DB_LOCK_DEADLOCK</a> or
throw a <a href="../api_cxx/deadlock_class.html">DbDeadlockException</a> exception.</p>
<p>If a Berkeley DB Concurrent Data Store database environment configured for lock timeouts was unable
to grant a lock in the allowed time, the DbEnv::dbremove method will fail and
either return <a href="../ref/program/errorret.html#DB_LOCK_NOTGRANTED">DB_LOCK_NOTGRANTED</a> or
throw a <a href="../api_cxx/lockng_class.html">DbLockNotGrantedException</a> exception.</p>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>
<br><b>See Also</b>
<a href="../api_cxx/env_list.html">Database Environments and Related Methods</a>
</tt>
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